This invention relates to poppet valves and more specifically to poppet valves utilized for communicating air pressure into a mold to eject the molded articles after molding.
A poppet valve such as that shown in the prior art drawing FIG. 1 has been utilized in the ejecting of molded articles by communicating air pressure to the valve as the mold opens. Difficulties have been encountered, such as axial angular displacement when the valve opens because of the lack of guidance for the poppet valve stem. Also, the cross pin which limits the movement of the poppet valve out of the valve seat is subjected by the spring to a cantilevered load which may bend the pin.
The present invention is directed to a poppet valve construction which prevents axial angular displacement as the valve opens and controls the axial linear displacement. The cross pin is also positioned to eliminate the cantilevered load on the pin by the spring.
In accordance with one aspect of the invention there is provided a poppet valve assembly comprising a valve body member having a valve seat, a poppet valve member for seating in the valve seat, orifices in the valve seat in communication with a source of air pressure, the poppet valve member having a valve stem extending through a cylindrical opening in the valve body member characterized by a cylindrical sleeve member having an outer diameter substantially the same as the diameter of the cylindrical opening in the valve body member with a length of reduced diameter providing a shoulder for engaging a spring and an inner diameter substantially the same as the diameter of the valve stem, the valve body having slots for receiving a cross pin extending through the valve stem and the sleeve member, and a coil spring interposed between the sleeve and the body member with the spring engageable with the shoulder for closing the poppet valve whereby the sleeve guides the valve stem and prevents axial angular displacement of the valve stem and the sleeve through its sliding fit over the valve stem provides a shear plane for forces applied to the cross pin.